For some reason, when tamed, these sheeps cause a glitch in the animals tab, their training tab is blank and they are causing an error that brings the game to a crawl:

System.NullReferenceException: Object reference not set to an instance of an object
at RimWorld.Pawn_TrainingTracker.CanAssignToTrain (RimWorld.TrainableDef,bool&) <0x00568>
at RimWorld.Pawn_TrainingTracker.CanAssignToTrain (RimWorld.TrainableDef) <0x0003e>
at RimWorld.StorytellerUtility.DefaultThreatPointsNow (RimWorld.IIncidentTarget) <0x00227>
at RimWorld.StorytellerUtility.DefaultSiteThreatPointsNow () <0x0003f>
at RimWorld.Planet.SiteMaker.MakeSite (RimWorld.SiteCoreDef,System.Collections.Generic.IEnumerable`1<RimWorld.SitePartDef>,int,RimWorld.Faction,bool,System.Nullable`1<single>) <0x00155>
at RimWorld.Planet.SiteMaker.MakeSite (RimWorld.SiteCoreDef,RimWorld.SitePartDef,int,RimWorld.Faction,bool,System.Nullable`1<single>) <0x0006f>
at MoreFactionInteraction.IncidentWorker_SpreadingOutpost.TryExecuteWorker (RimWorld.IncidentParms) <0x00167>
at (wrapper dynamic-method) RimWorld.IncidentWorker.TryExecute_Patch1 (object,RimWorld.IncidentParms) <0x00024>
at RimWorld.Storyteller.TryFire (RimWorld.FiringIncident) <0x0008e>
at RimWorld.IncidentQueue.IncidentQueueTick () <0x000c4>
at RimWorld.Storyteller.StorytellerTick () <0x0002f>
at Verse.TickManager.DoSingleTick () <0x00610>

Verse.Log:Error(String, Boolean)
Verse.TickManager:DoSingleTick()
Verse.TickManager:TickManagerUpdate()
Verse.Game:UpdatePlay()
Verse.Root_Play:Update()